SENSITIVITY OF VARIOUS FOLIAGE AND FLOWERING POTTED PLANTS TO ETHYLENE

Experiments were performed to determine the sensitivity of over 50 species of ornamental potted plants to exogenous ethylene. Plants were exposed to 0 to 15 μl/1 ethylene during 72 hours at 20°C in the dark. It was shown that the most significant toxicity symptoms on foliage plants were abscission and yellowing of leaves. Flowering plants showed abscission of flowers, flower buds or of whole inflorescences. In general, abscission of leaves was only observed when plants were exposed to ethylene for 72 hours while abscission of flowers and flower buds appeared after only 24 hours of ethylene treatment. Species were divided in classes of ethylene sensitivity. It was shown that the economically most interesting species were less sensitive to ethylene than the economically uninteresting ones.